Q: Dear Tom and Ray:

A few months ago, you had an article in your column about replacing timing belts on Nissans after 60,000 miles. Since I have a '92 Nissan Sentra XE that has 72,000 miles, I decided to get mine replaced so I wouldn't get stranded. Also, I had received mail from the local Nissan dealer recommending replacement of the timing belt after 60,000 miles. After discussing this with my husband, brother and other male friends, they agreed that I should have it done. I made an appointment at the local dealer and arranged to have my sister-in-law wait for me in the parking lot so she could give me a ride home.

The guy who was writing up my service order went to get my car, and after 10 minutes he reappeared and said, "Ma'am, you don't have a timing belt. They switched over to chains in 1988, and that's what they use now." After a brief discussion, I went out to the parking lot and told my sister-in-law, "I don't have a timing belt." "Well," she said, "did they tell you to bring your own?"

At this point, I was beginning to feel the frustration of the situation, but after a few minutes we began to see the humor in it. My sister-in-law Anne told me, "It's women like you who give us a bad name when it comes to cars." To which I responded that a half a dozen men had agreed with me on this one. Just thought you'd enjoy the story!

-- Dottie

A: TOM: We did, Dottie! Thank you. While it's true that many, if not most, cars now use timing belts, some cars--and yours is one of them--use timing chains.

RAY: Belts are favored these days because they're cheaper, lighter, quieter and easier to replace. But a good number of cars have gone back to timing chains, which have the advantage of not needing to be changed until they break . . . which may be never. But if a timing chain does break, it's a much bigger job to replace it.

TOM: There are advantages and disadvantages to both systems, so I wouldn't base a future car-buying decision on it. You just have what you have, and if you have a belt, you have to make sure it's changed at the recommended interval.

RAY: But how would you know which one you have, Dottie? Not only had half a dozen men agreed with you, but the folks at the dealership even sent you a notice telling you to come in and have it done! They should have told you that you don't need a timing belt when you called to make an appointment.

TOM: Hold your head high, Dottie. I'd say you're clearly off the hook here. But for those of you who don't want to end up in Dottie's situation in the future, check your owner's manual.

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1999 by Tom and Ray Magliozzi and Doug Berman